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FE Power Forums => Non-FE Discussion Forum => Topic started by: whitea62.7t on April 11, 2016, 05:30:56 PM

Title: Help
Post by: whitea62.7t on April 11, 2016, 05:30:56 PM
I know this isnt an FE
But the brain power on this site is unmatched
Took the valve cover off and found this
Head bolt between #2 and #3 cylinder broke
Anyone know from the pic , what may have caused this
It broke off below the surface , do i need to pull the head , of does anyone think an easy-out would work
Thank you in advance for any help
Sean
Title: Re: Help
Post by: Heo on April 11, 2016, 07:04:56 PM
Embrittelment due to fatigue most likely.
Happens some times. whats left of it in
the block is most likely easy to get out
if you get a grip of it.Left hand twisted
drillbits often work.
I do it like this i drill it with LH twisted drillbit
if that dont get it out i pound a Torx bit in
the drilled hole and screw it out
Title: Re: Help
Post by: whitea62.7t on April 11, 2016, 07:18:57 PM
Its sunk below the head , cant tell if its below the deck
Title: Re: Help
Post by: Heo on April 11, 2016, 07:29:22 PM
11 times of 10 ;)it breaks just below deck
surface
Title: Re: Help
Post by: cjshaker on April 11, 2016, 08:27:25 PM
It could have just been a faulty bolt. I've pulled a pan off to find a busted main bolt before. The corrosion on the fractured part indicated that it had been busted for some time. That was on an untouched original engine that ran until the 2nd bolt busted and sent the main cap flying through the oil pan.

I deal with this stuff all the time at work. Sometimes it can be as easy as getting a small screwdriver in there and gently wedging it and turning it until it comes out, sometimes I use a small pick to get it to twist out, or a reverse bit as Heo said. Anything that will get it to turn basically. I've even used a strong magnet on a telescoping rod before. You know, the type that is intended to retrieve things in tight spots? The bolt isn't tightened anymore, so it should turn easily. I'm usually successful, but that's not always the case and sometimes they just refuse to turn no matter how hard I try.
Title: Re: Help
Post by: machoneman on April 11, 2016, 09:19:34 PM
Another theory! Unless you know otherwise, a rebuilder engine or one done by a sloppy mechanic using a impact wrench as his torque wrench (!) could easily have way over-torqued head bolts. For that reason alone I'd pop BOTH heads and use all new head bolts. And yes, gaskets as well.

Sadly it the rebuilder jinx is true, the rod, main and other bolts could also be past yield strength. Btw, I've never seen a head bolt break like that on any engine unless something was amiss when it was tightened down.   
Title: Re: Help
Post by: whitea62.7t on April 18, 2016, 04:02:49 PM
Well left handed drill bits , work wonders
Title: Re: Help
Post by: Heo on April 18, 2016, 04:12:54 PM
Im glad i could help you
Title: Re: Help
Post by: whitea62.7t on April 19, 2016, 05:34:11 PM
If i could bother everyone with another 302 question
launched the car , shifted at 5600
made a load boom and died
thought i blew the motor , no holes , pulled the valve covers , everything looked ok
Pulled the car and the tab inside the rotor button broke off
Replaced it  and the timing is way off , had to move it 1/3 turn , and she fired right up
Does it sound like timing chain jump a tooth or 2?
Thank you for your help
Title: Re: Help
Post by: thatdarncat on April 19, 2016, 06:47:49 PM
You may have sheared the roll pin holding the gear on the distributor shaft. I have seen where the roll pin shears, the gear moves a certain amount and stops. If that is the case under a hard load the gear may shift again.
Title: Re: Help
Post by: whitea62.7t on April 20, 2016, 07:41:09 AM
Pulled the distributor , pin and gear are all good
gong to have to pull the timing cover, grr
Jay , hope you don't mind me asking non-fe questions here , this is the only site , that isn't full of people who "think" they know what they are doing
Everyone here seems very knowledgeable and helpful
Some day when funds allow the 302 will be pulled for a stroker FE in this
Title: Re: Help
Post by: Heo on April 20, 2016, 08:33:57 AM
Maby the tab in the rotor was on its way to fail when you
set the timing last time. And now it failed completly,
if its the tab that "drive" the rotor we are talking about.
If the chain jump one or two tooths the engine is not
running like it should even if you set the timing
Title: Re: Help
Post by: whitea62.7t on April 20, 2016, 12:19:57 PM
Yes it was the tab on the inside on the duraspark  rotor
Checked the compression  all between 130-150
I bought the car , didnt build the engine myself
reset the distributor , Hope thats the problem
Title: Re: Help
Post by: jayb on April 20, 2016, 01:20:33 PM

Jay , hope you don't mind me asking non-fe questions here , this is the only site , that isn't full of people who "think" they know what they are doing
Everyone here seems very knowledgeable and helpful


No problem, that is what the non-FE board is for.  Questions about any engine are welcome - Jay
Title: Re: Help
Post by: Heo on April 20, 2016, 02:58:58 PM
If the engine runs fine likely that was the problem
The question is how could the tab get broken?
Is the rotor hitting the cap? to much endplay
on the dist.?
Title: Re: Help
Post by: whitea62.7t on April 20, 2016, 03:06:20 PM
No the rotor isnt to close ,Just pulled the timing cover , almost an inch play on the slack side of the chain
Ordering a new 1 now
Thank you for all your help
You guys are a great help
Title: Re: Help
Post by: whitea62.7t on April 22, 2016, 09:38:31 PM
Have the timing chain in
set the timing , its a locked out duraspark
runs great at 30 degrees
whenever i hit the throttle it back fires thru the carb
any ideas?
Title: Re: Help
Post by: whitea62.7t on April 23, 2016, 09:02:56 AM
Ok , This isnt good , did a compression test again and #8 cyl , filled the hose and gauge with gas